The present invention relates to highly concentrated, stable pharmaceutical formulations of a pharmaceutically active anti-HER2 antibody or a mixture of such antibody molecules for subcutaneous injection. Such formulations comprise, in addition to the high amounts of anti-HER2 antibody or mixture thereof, a buffering agent, a stabilizer or a mixture of two ore more stabilizing agents, a nonionic surfactant and an effective amount of at least one hyaluronidase enzyme. The invention also relates to a process for the preparation of the said formulation and to the uses of such formulation.
The pharmaceutical use of antibodies has increased over the past years. In many instances such antibodies are injected via the intravenous (IV) route. Unfortunately the amount of antibody that can be injected via the intravenous route is limited by the physico-chemical properties of the antibody, in particularly by its solubility and stability in a suitable liquid formulation and by the volume of the infusion fluid. Alternative administration pathways are subcutaneous or intramuscular injection. These injection pathways require high protein concentration in the final solution to be injected [Shire, S. J., Shahrokh, Z. et al., “Challenges in the development of high protein concentration formulations”, J. Pharm. Sci. 2004; 93(6): 1390-1402; Roskos, L. K., Davis C. G. et al., “The clinical pharmacology of therapeutic antibodies”, Drug Development Research 2004; 61(3): 108-120]. In order to increase the volume, and thereby the therapeutic dose, which can be safely and comfortably administered subcutaneously it has been proposed to use glycosaminoglycanase enzyme(s) in order to increase the interstitial space into which the antibody formulation can be injected [WO2006/091871].
Examples of stable formulations of pharmaceutically active antibodies for therapeutic use currently on the market are as follows:
HERCEPTIN™ (Trastuzumab) is a monoclonal antibody directed against the HER2 receptor (anti HER2 antibody) which is currently marketed in Europe in form of a 150 mg lyophilized powder (containing the antibody, α,α-trehalose dihydrate, L-histidine and L-histidine hydrochloride and polysorbate 20) which is reconstituted for infusions with water for injection to yield an injection dose of approximately 21 mg/ml. In the USA and many other countries a multiple dosage vial containing 440 mg Trastuzumab is marketed.
AVASTIN™ (Bevacizumab) is a monoclonal antibody directed against the vascular endothelial growth factor (VEGF) which is currently marketed in Europe as a liquid formulation in two types of vials: a) 100 mg Bevacizumab in 4 ml and b) 400 mg Bevacizumab in 16 ml, respectively, providing a final concentration of 25 mg/ml in water for injection containing the following excipients: trehalose dihydrate, sodium phosphate and polysorbate 20.
While the above antibody formulations have been found suitable for intravenous administration there is a desire to provide highly concentrated, stable pharmaceutical formulations of therapeutically active antibodies for subcutaneous injection. The advantage of subcutaneous injections is that it allows the medical practitioner to perform it in a rather short intervention with the patient. Moreover the patient can be trained to perform the subcutaneous injection by himself. Such self-administration is particularly useful during maintenance dosing because no hospital care is needed (reduced medical resource utilization). Usually injections via the subcutaneous route are limited to approximately 2 ml. For patients requiring multiple doses, several unit dose formulations can be injected at multiple sites of the body surface.
The following two antibody products for subcutaneous administration are already on the market.
HUMIRA™ (Adalimumab) is a monoclonal antibody directed against tumor necrosis factor alpha (TNF alpha) which is currently marketed in Europe in form of a 40 mg dose in 0.8 ml injection volume for subcutaneous application (concentration: 50 mg antibody/ml injection volume).
XOLAIR™ (Omalizumab) a monoclonal antibody directed against immunoglobulin E (anti IgE antibody) which is currently marketed in form of a 150 mg lyophilized powder (containing the antibody, sucrose, histidine and histidine hydrochloride monohydrate and polysorbate 20) which is be reconstituted with water for subcutaneous injection to yield a 125 mg/ml injection dose.
No highly concentrated, stable pharmaceutical anti-HER2 antibody formulation suitable for subcutaneous administration is currently available on the market. There is therefore a desire to provide such highly concentrated, stable pharmaceutical formulations of therapeutically active antibodies for subcutaneous injection.
The injection of parenteral drugs into the hypodermis is generally limited to volumes of less than 2 ml due to the viscoelastic resistance to hydraulic conductance in the subcutaneous (SC) tissue, due to the generated backpressure upon injection [Aukland K. and Reed R., “Interstitial-Lymphatic Mechanisms in the control of Extracellular Fluid Volume”, Physiology Reviews”, 1993; 73:1-78], as well as due to the perceptions of pain.
The preparation of high concentration protein formulations is rather challenging and there is a need to adapt each formulation to the particular proteins used because each protein has a different aggregation behavior. Aggregates are suspected to cause immunogenicity of therapeutic proteins in at least some of the cases. Immunogenic reaction against protein or antibody aggregates may lead to neutralizing antibodies which may render the therapeutic protein or antibody ineffective. It appears that the immunogenicity of protein aggregates is most problematic in connection with subcutaneous injections, whereby repeated administration increases the risk of an immune response.
While antibodies have a very similar overall structure, such antibodies differ in the amino acid composition (in particular in the CDR regions responsible for the binding to the antigen) and the glycosylation pattern. Moreover there may additionally be post-translational modifications such as charge and glycosylation variants. In the particular case of anti-HER2 antibodies such post-translational modifications have been described e.g. for the humanized monoclonal antibody humMAb4D5-8 (=Trastuzumab). Particular purification methods for the removal of e.g. acidic variants have been developed and compositions comprising a reduced amount of acidic variants (predominantly deamidated variants wherein one or more asparagine residue(s) of the original polypeptide have been converted to aspartate, i.e. the neutral amide side chain has been converted to a residue with an overall acidic character) have first been provided by Basey, C. D and Blank, G. S. in WO99/57134.
Stable lyophilized antibody formulations comprising a lyoprotectant, a buffer and a surfactant have been described by Andya et al. (WO 97/04801 and U.S. Pat. Nos. 6,267,958, 6,685,940, 6,821,151 and 7,060,268).
WO 2006/044908 provides antibody formulations, including monoclonal antibodies formulated in histidine-acetate buffer, pH 5.5 to 6.5, preferably 5.8 to 6.2.
The problem to be solved by the present invention is therefore to provide novel highly concentrated, stable pharmaceutical formulations of a pharmaceutically active anti-HER2 antibody or a mixture of anti-HER2 antibody molecules for subcutaneous injection. Such formulations comprise, in addition to the high amounts of anti-HER2 antibody or anti-HER2 antibody mixture, a buffering agent, a stabilizer or a mixture of two or more stabilizers, a nonionic surfactant and an effective amount of at least one hyaluronidase enzyme. The preparation of highly-concentrated antibody formulations is challenging because of a potential increase in viscosity at higher protein concentration and a potential increase in protein aggregation, a phenomenon that is per se concentration-dependent. High viscosities negatively impact the process ability (e.g. pumping and filtration steps) of the antibody formulations and the administration (e.g. the syringe ability). By the addition of excipients high viscosities could be decreased in some cases. Control and analysis of protein aggregation is an increasing challenge. Aggregation is potentially encountered during various steps of the manufacturing process, which include fermentation, purification, formulation and during storage. Different factors, such as temperature, protein concentration, agitation stress, freezing and thawing, solvent and surfactant effects, and chemical modifications, might influence the aggregation behavior of a therapeutic protein. During development of a highly concentrated antibody formulation the aggregation tendency of the protein has to be monitored and controlled by the addition of various excipients and surfactants [Kiese S. et al., J. Pharm. Sci., 2008; 97(10); 4347-4366]. The challenge to prepare suitable highly concentrated, stable pharmaceutical formulation of the pharmaceutically active anti-HER2 antibody in accordance with the present invention is increased by the fact that two different proteins have to be formulated in one liquid formulation in such a way that the formulation remains stable over several weeks and the pharmaceutically active ingredients remain active during proper storage.